refactor: replace .env.example with .env.template in documentation

- Remove volumes/env/.env.example file
- Update all documentation references to use .env.template instead
- Update bootstrap script error message
- Update .gitignore comment

volumes/env/.env.example

@@ -1,40 +0,0 @@
-# FuzzForge Agent Configuration
-# Copy this to .env and configure your API keys and proxy settings
-
-# LiteLLM Model Configuration (default routed through the proxy)
-LITELLM_MODEL=openai/gpt-5
-LITELLM_PROVIDER=openai
-# Leave empty to let bootstrap mirror the LiteLLM model list dynamically.
-LITELLM_DEFAULT_MODELS=
-
-# Proxy configuration
-# Base URL is used by the task agent to talk to the proxy container inside Docker.
-# When running everything locally without Docker networking, replace with http://localhost:10999.
-FF_LLM_PROXY_BASE_URL=http://llm-proxy:4000
-
-# Virtual key placeholder. The bootstrap job replaces this with a LiteLLM
-# proxy-issued key on startup so the task agent authenticates via the gateway.
-OPENAI_API_KEY=sk-proxy-default
-
-# LiteLLM proxy configuration
-LITELLM_MASTER_KEY=sk-master-key
-LITELLM_SALT_KEY=choose-a-random-string
-# LiteLLM UI login (defaults to admin/fuzzforge123 if not overridden)
-UI_USERNAME=fuzzforge
-UI_PASSWORD=fuzzforge123
-# Optional: override OTEL exporter endpoint if using a remote collector
-# OTEL_EXPORTER_OTLP_ENDPOINT=http://otel-collector:4317
-# LITELLM_DEFAULT_KEY_BUDGET=25
-# LITELLM_DEFAULT_KEY_DURATION=7d
-
-# Upstream provider secrets (ingested by the proxy only). The bootstrapper copies
-# these into volumes/env/.env.litellm so other containers never see the raw keys.
-# LITELLM_OPENAI_API_KEY=
-# LITELLM_ANTHROPIC_API_KEY=
-# LITELLM_GEMINI_API_KEY=
-# LITELLM_MISTRAL_API_KEY=
-# LITELLM_OPENROUTER_API_KEY=
-
-# Agent behaviour
-# DEFAULT_TIMEOUT=120
-# DEFAULT_CONTEXT_ID=default